Thoroughbreds are a breed of horse known for their agility, speed, and spirit, often associated with horse racing and equestrian sports. Originating from crossbreeding native English mares with imported Arabian, Barb, and Turkoman stallions, Thoroughbreds have a well-documented pedigree that traces back to the late 17th and early 18th centuries. This breed is characterized by a refined head, deep chest, and long legs, contributing to their athletic capabilities. Thoroughbreds are primarily bred for their performance in racing but are also utilized in other equestrian disciplines. This page compiles peer-reviewed research studies and scholarly articles that explore the genetics, physiology, and performance characteristics of Thoroughbreds, as well as their management and welfare in various equine activities.
Scoggin CF.Advancing age can adversely affect a thoroughbred brood-mare's reproductive efficiency and influence the commercial and athletic potential of her progeny. Causes for the decline in fertility include decreased oocyte and embryo quality, anatomical defects and endometrial degeneration. In addition, evidence exists that as the age of a dam increases, her foals will be at increased risk of morbidity and mortality during the neonatal period. Health issues can have lasting and deleterious effects on surviving foals, including decreased sale value and reduced athletic performance. The purpose of this...
Jones B, Goodfellow J, Yeates J, McGreevy PD.There is increasing controversy about the use of the whip as a performance aid in Thoroughbred horseracing and its impact on horse welfare. This paper offers a critical analysis of the British Horseracing Authority's (BHA) 2011 Report Responsible Regulation: A Review of the Use of the Whip in Horseracing. It examines the BHA's process of consultation and use of science and public opinion research through the application of current scientific literature and legal analysis. This analysis suggests that the BHA's findings on the welfare impact and justification for whip use are insufficiently defe...
Sinatra ST, Caiazzo C.d-Ribose is a popular dietary supplement for humans and the equine because of its crucial role in cellular bioenergetics. However, as a reducing sugar, it has been suggested that ingestion of d-ribose might promote the formation of glycated proteins in vivo with potential adverse consequences. Objective: The aim of this study was to examine if d-Ribose would promote the formation of glycated proteins in vivo following exercise in training thoroughbred racehorses. Methods: Two groups of horses received the supplement (30 and 50 g d-Ribose daily) for 17 weeks, during which period the horses were...
Bani Hassan E, Mirams M, Ghasem-Zadeh A, Mackie EJ, Whitton RC.To gain a better understanding of the aetiology of articular surface collapse in horses with palmar osteochondral disease. Objective: To determine whether acceleration of focal bone resorption associated with reduced physical activity contributes to articular surface collapse in racehorses with palmar osteochondral disease. Methods: Cross-sectional study comparing metacarpal bones from horses at varying stages of race training. Methods: Metacarpal bones from 36 racing Thoroughbred horses were examined with high-resolution peripheral quantitative computed tomography to determine the proportion ...
Schnabel CL, Steinig P, Schuberth HJ, Koy M, Wagner B, Wittig B, Juhls C, Willenbrock S, Murua Escobar H, Jaehnig P, Feige K, Cavalleri JM.Leukocytes and their functional capacities are used extensively as biomarkers in immunological research. Commonly employed indicators concerning leukocytes are as follows: number, composition in blood, response to discrete stimuli, cytokine release, and morphometric characteristics. In order to employ leukocytes as biomarkers for disease and therapeutic monitoring, physiological variations and influencing factors on the parameters measured have to be considered. The aim of this report was to describe the ranges of selected leukocyte parameters in a sample of healthy horses and to analyse wheth...
Peloso JG, Vogler JB, Cohen ND, Marquis P, Hilt L.To compare bony changes in the metacarpophalangeal joint (MCPJ) of racehorses with (cases) and without (controls) biaxial proximal sesamoid bone (PSB) fracture as determined by 2 grading scales applied to images of cadaveric forelimbs obtained by means of standing MRI (sMRI). Methods: Case-control study. Methods: Forelimbs from 74 Thoroughbred racehorses (21 cases and 53 controls) that were euthanized at a Florida racetrack. Methods: Both forelimbs were harvested from cases and controls. Each forelimb underwent sMRI to obtain images of the MCPJ. Two grading scales were described and used for i...
Duz M, Parkin TD, Cullander RM, Marshall JF.To evaluate ex vivo cyclooxygenase (COX) inhibition and compare in vitro and ex vivo COX-1 inhibition by flunixin meglumine and firocoxib in horses. Methods: 4 healthy horses for in vitro experiments and 12 healthy horses (6 males and 6 females; 5 Thoroughbreds, 5 Warmbloods, and 2 ponies) undergoing elective surgery for ex vivo experiments. Methods: 12 horses received flunixin meglumine (1.1 mg/kg, IV, q 12 h) or firocoxib (0.09 mg/kg, IV, q 24 h). Blood samples were collected before (baseline) and 2 and 24 hours after NSAID administration. Prostanoids (thromboxane B2, prostaglandin E2, and p...
David F, Levingstone TJ, Schneeweiss W, de Swarte M, Jahns H, Gleeson JP, O'Brien FJ.An unmet need remains for a bone graft substitute material that is biocompatible, biodegradable and capable of promoting osteogenesis safely in vivo. The aim of this study was to investigate the use of a novel collagen-hydroxyapatite (CHA) bone graft substitute in the clinical treatment of a mandibular bone cyst in a young horse and to assess its potential to enhance repair of the affected bone. A 2 year-old thoroughbred filly, presenting with a multilobulated aneurysmal bone cyst, was treated using the CHA scaffold. Post-operative clinical follow-up was carried out at 2 weeks and 3, 6 and...
Bolwell CF, Rosanowski SM, Scott I, Sells PD, Rogers CW.Against a global background of increasing anthelmintic resistance in parasites, little is known about the current parasite control strategies adopted within the equine industry in New Zealand. The aim of the study was to describe and compare the current parasite management and control practices used on Thoroughbred and Standardbred stud farms in New Zealand. An online questionnaire was used to collect data on the demographics of respondents, parasite control methods, grazing management, and use of faecal egg counts. Questions regarding parasite control strategy, how often horses were dewormed,...
Raffetto JA, Wearn JG, Fischer AT.Recurrent laryngeal neuropathy (RLN) causes airway obstruction and adversely affects racing performance in Thoroughbred racehorses. Prosthetic laryngoplasty (PL) is the preferred treatment of RLN as it returns variables of airway mechanics to baseline. A number of materials have been evaluated as prostheses; however, the application of Lycra has not been rigorously investigated. Objective: To evaluate the efficacy of PL using a Lycra prosthesis, in combination with transendoscopic, laser-assisted ventriculocordectomy, to restore racing performance in Thoroughbred racehorses with RLN. Methods: ...
Sykes BW, Underwood C, McGowan CM, Mills PC.The objectives of this study were to investigate the impact of formulation (enteric coated and buffered) and feeding on pharmacokinetic variables associated with the oral administration of omeprazole in the horse. Six thoroughbred racehorses were studied in a crossover design. Each received 2 g of an enteric coated or buffered formulation in both the fed and fasted state. Plasma omeprazole concentrations were determined by UHPLC-MS. The effects of feeding or formulation on AUC0-inf_obs, half-life, Tmax or Cmax were not statistically significant. However, a wider-than-expected degree of variati...
Szarska E, Cywińska A, Ostaszewski P, Kowalska A.The purpose of this study was to compare the training methods used in two stables and their effects on selected blood parameters and race results. A total number of 36 thoroughbred race horses was examined in two groups, trained by two trainers. Twenty-four horses (group A) were trained at Sluzewiec and the remaining twelve horses (group B) were kept and trained in a private stable. The experiment lasted for five months. The activities of CPK (creatine phosphokinase) and AST (aspartate aminotransferase) and the concentration of LA (lactic acid) were determined. The speed was controlled and rec...
Korosue K, Endo Y, Murase H, Ishimaru M, Nambo Y, Sato F.Flexural deformities are common conditions of growing horses and are suggested to have a relationship with the contraction of musculotendinous units. However, limited studies have documented the changes in each tendon and ligament in the metacarpal region with age. Objective: To investigate the changes in the cross-sectional area (CSA) of each tendon and ligament in the metacarpal region with age by ultrasonographic examination. Methods: Longitudinal study of foals from Day 1 to age 24 months. Methods: The CSA of the superficial digital flexor tendon, deep digital flexor tendon, accessory liga...
Sullivan SL, Whittem T, Morley PS, Hinchcliff KW.Furosemide is the most commonly used medication for exercise-induced pulmonary haemorrhage (EIPH); however, critical evaluation of the strength of evidence for efficacy of furosemide is lacking and is warranted so that evidence-based treatment decisions can be made. Objective: To evaluate the efficacy of furosemide to reduce the severity or frequency of detection of EIPH in Thoroughbred and Standardbred racehorses. Methods: Systematic review with meta-analyses. Methods: Primary studies were identified via searches of electronic databases, relevant texts and reference lists of published article...
Gim JA, Hong CP, Kim DS, Moon JW, Choi Y, Eo J, Kwon YJ, Lee JR, Jung YD, Bae JH, Choi BH, Ko J, Song S, Ahn K, Ha HS, Yang YM, Lee HK, Park KD....Athletic performance is an important criteria used for the selection of superior horses. However, little is known about exercise-related epigenetic processes in the horse. DNA methylation is a key mechanism for regulating gene expression in response to environmental changes. We carried out comparative genomic analysis of genome-wide DNA methylation profiles in the blood samples of two different thoroughbred horses before and after exercise by methylated-DNA immunoprecipitation sequencing (MeDIP-Seq). Differentially methylated regions (DMRs) in the pre-and post-exercise blood samples of superio...
Escalona EE, Leng J, Dona AC, Merrifield CA, Holmes E, Proudman CJ, Swann JR.Metabonomics is emerging as a powerful tool for disease screening and investigating mammalian metabolism. This study aims to create a metabolic framework by producing a preliminary reference guide for the normal equine metabolic milieu. Objective: To metabolically profile plasma, urine and faecal water from healthy racehorses using high resolution (1) H-nuclear magnetic resonance (NMR) spectroscopy and to provide a list of dominant metabolites present in each biofluid for the benefit of future research in this area. Methods: This study was performed using 7 Thoroughbreds in race training at a ...
Gim JA, Lee S, Kim DS, Jeong KS, Hong CP, Bae JH, Moon JW, Choi YS, Cho BW, Cho HG, Bhak J, Kim HS.With the advent of next-generation sequencing technology, genome-wide maps of DNA methylation are now available. The Thoroughbred horse is bred for racing, while the Jeju horse is a traditional Korean horse bred for racing or food. The methylation profiles of equine organs may provide genomic clues underlying their athletic traits. We have developed a database to elucidate genome-wide DNA methylation patterns of the cerebrum, lung, heart, and skeletal muscle from Thoroughbred and Jeju horses. Using MeDIP-Seq, our database provides information regarding significantly enriched methylated regions...
Mahaffey CA, Peterson ML, Thomason JJ, McIlwraith CW.Different horseshoe designs have been developed in an attempt to optimise footing for equine athletes. Horseshoe performance is assumed to be dependent on the surface and gait, but there are limited data on horseshoe performance on different surfaces, independent of gait variation. Objective: To quantify the dynamic loading for 3 aluminium racing shoe designs on Thoroughbred racetrack surface materials, using a biomechanical surface tester. Methods: A flat racing plate, a serrated V-Grip and a shoe with a 6 mm toe grab and 10 mm heel calks were tested on synthetic and dirt surfaces under t...
Okai K, Taharaguchi S, Orita Y, Yokota H, Taniyama H.To contribute to early diagnosis and treatment of gastric ulcer of foals, we examined the gastric mucosa of healthy and affected foals using an endoscope. In healthy foals, the characteristic changes in the development of the squamous mucosa were seen mainly in the squamous mucosa, and maturation of the squamous mucosa in the greater curvature (GC-S) occurred more slowly than that of the squamous mucosa in the lesser curvature (LC-S). Epithelial desquamation in the LC-S and GC-S was observed between 6 and 90 days but was not observed in the LC-S at about 60 days, whereas it was observed in the...
Knych HK, Arthur RM, McKemie DS, Chapman N.Flunixin meglumine is commonly used in horses for the treatment of musculoskeletal injuries. The current ARCI threshold recommendation is 20 ng/mL when administered at least 24 h prior to race time. In light of samples exceeding the regulatory threshold at 24 h postadministration, the primary goal of the study reported here was to update the pharmacokinetics of flunixin following intravenous administration, utilizing a highly sensitive liquid chromatography-mass spectrometry (LC-MS). An additional objective was to characterize the effects of flunixin on COX-1 and COX-2 inhibition when drug con...
Shepard MK, Lee WL, Eggleston RB.A 21-year-old Thoroughbred gelding with a history of equine pituitary pars intermedia dysfunction (PPID) presented with priapism of 2 days' duration. The horse received a caudal morphine epidural and then underwent corpus cavernosum lavage and phallectomy under general anesthesia. The patient's recovery featured multiple unsuccessful attempts to stand and his respiratory distress persisted for several hours until he acutely developed severe colic and was euthanized. Necropsy findings revealed a pituitary adenoma of the pars intermedia, bilateral adrenal cortical hyperplasia, and diaphragmatic ...
Barsuren E, Namkhai B, Kong HS.The objective of this study was to assess differences in serum protein expression profiles of Przewalski's (Mongolian wild horse) and thoroughbred horses using proteome analysis. The serum proteins were separated by two-dimensional electrophoresis (2-DE) and five different gene products were identified. Proteins represented by the five spots were identified by matrix-assisted laser desorption ionization-time-of-flight (MALDI-TOF) mass spectrometry (MS)/MS technology. The identities of all proteins were deduced based on their similarity to proteins in the human plasma protein database. Three pr...
Miller CA, Durham AC, Schaffer PA, Ehrhart EJ, Powers BE, Duncan CG.Equine cutaneous lymphoma is an uncommon disease that can present with variable clinical signs, immunosuppression, and rapid systemic disease progression. Various subtypes of equine lymphoma have been described and classified according to a veterinary adaptation of the World Health Organization classification system, but little data is available regarding the association between lymphoma subtypes and epidemiological criteria and/or clinical outcome. The objective of the current study was to classify previously diagnosed cases of equine cutaneous lymphoma and correlate subtypes with clinical da...
Robert M, Hu W, Nielsen MK, Stowe CJ.Traditionally, equine parasite control has relied heavily on frequent routine anthelmintic treatments applied at regular intervals all year round. However, current recommendations aim to employ a more surveillance-based approach and it remains unknown to what extent these recommendations are being implemented on US horse farms. Objective: To describe equine parasite control on Kentucky Thoroughbred farms and evaluate respondents' willingness to pay for various attributes of surveillance-based parasite control strategies. Methods: Questionnaire survey performed among the membership of the Kentu...
Faramarzi B, McMicking H, Halland S, Kaneps A, Dobson H.Recent studies indicate a high prevalence of fractures of the palmar processes (PP) of the distal phalanx in foals. However, information on the prevalence of such fractures in different breeds and the effect of predisposing factors, such as hoof conformation, is limited. Objective: To examine the prevalence of distal phalanx PP fractures in foals and report the relationship of distal limb and hoof conformation with the prevalence of fracture. Methods: Longitudinal study. Methods: Front hooves of 19 Thoroughbred, Quarter Horse and Arabian foals were examined. Digital radiographic and photograph...
Endo Y, Tsuchiya T, Akiyama K, Takebe N, Nakai K, Korosue K, Ishimaru M, Tsuzuki N, Hobo S.In order to reveal the preventive effect of marbofloxacin (MRFX) administration just before transportation, we compared the occurrence of transportation-associated fever before and after introduction of MRFX administration. After the introduction of prophylactic MRFX administration, the rectal temperatures of horses after transportation were significantly lower than before the introduction of MRFX administration (P<0.01) and the number of febrile horses was significantly lower than before the introduction of MRFX administration (P<0.01). In conclusion, these results show that prophylacti...
Takahashi T, Matsui A, Mukai K, Ohmura H, Hiraga A, Aida H.It is important to know the effects of the inclination of a slope on the activity of each muscle, because training by running on a sloped track is commonly used for Thoroughbred racehorses. The effects of incline (from -6 to +6%) on the forelimbs and hind limbs during walking and trotting on a treadmill were evaluated by an integrated electromyogram (iEMG). The muscle activities in the forelimbs (5 horses) and hind limbs (4 horses) were measured separately. Two stainless steel wires were inserted into each of the brachiocephalicus (Bc), biceps brachii (BB), splenius (Sp), and pectoralis descen...
Hill AE, Gardner IA, Carpenter TE, Lee CM, Hitchens PL, Stover SM.Knowledge of the site distribution of ligamentous injuries facilitates clinical diagnosis of suspensory apparatus conditions. Objective: To determine if lesions within the suspensory ligament (SL) and distal ligaments of the proximal sesamoid bones (DSLs) were associated with suspensory apparatus failure or metacarpal lateral condylar fracture in California Thoroughbred racehorses. Methods: Cross-sectional study. Methods: Suspensory apparatus specimens from 327 deceased Thoroughbred racehorses were sectioned within the SL body and branches, and oblique and straight DSLs. Purple lesions ≥2 ...
Merkt H, Günzel AR.Embryonic resorption is reported as the main reason for early pregnancy losses in the West German Thoroughbred mare. An analysis of breeding records for the last 11 years showed a resorption rat of 8.4 per cent. Evidence was obtained that these early embryonic losses were associated with too early conception after foaling and with the state of lactation.
Parsons KJ, Pfau T, Ferrari M, Wilson AM.During locomotion on an incline, mechanical work is performed to move an animal up the slope and increase the potential energy (PE) of the trunk and hence the centre of mass (CoM). Thus, at a given speed the total net mechanical work increases with the PE of the animal. In this study we investigate the mechanical energy (ME) fluctuations and the mechanical cost of transport (MCT) in six horses galloping up a range of gradients. We captured trunk movement with a six degrees-of-freedom inertial sensor mounted over the dorsal spinous process of the fourth to sixth thoracic vertebrae of the horse....
Bogers SH, Rogers CW, Bolwell CF, Roe WD, Gee EK, McIlwraith CW.The aim of the study was to use spatial and multiple correspondence analysis (MCA) to describe and compare the regional proportion and spatial pattern of volumetric bone mineral density (BMDv) values within loaded regions of the plantar metatarsal epiphysis of young horses in race training. A single 2 mm transverse peripheral quantitative computed tomography 'slice', 10 mm proximal from the distal limit of the sagittal ridge of the distal metatarsal epiphysis was obtained from 14 2-year-old Thoroughbred fillies (7 exercised and 7 controls). Six regions of interest were generated and examin...
Lavoie JP, Pascoe JR, Kurpershoek CJ.We studied the temporal changes in respiratory mechanics associated with xylazine administration (1.1 mg/kg of body weight, IV) in standing horses (experiment 1), and determined the effects of head and neck position (experiment 2) and atropine administration (experiment 3) on the observed changes. Thoroughbred geldings, 3 to 5 years old (5 in experiment 1, 4 in experiments 2 and 3) were used. Flow rates were obtained from a pneumotachograph and a differential transducer attached to a tight-fitting mask. Electronic integration of the flow signal gave tidal volume. Total pulmonary pressure (PL) ...
Chen CL, Sailor JA, Collier J, Wiegand J.Seven mature thoroughbred horses, weighing between 400 and 541 kg, were each injected intra-articularly into three joints with 6 mg/joint of triamcinolone acetonide (Vetalog). The fourth joint, the control, was injected with saline. Synovial fluid was taken from all four legs of the horses on days 1, 2, 3, 4, 5, 6, 7, 8, 11, and 15 following the injections. Triamcinolone acetonide was assayed by a radioimmunoassay. Blood was collected at 1, 2, 4, 6, 12 h and on days 1, 2, 3, 4, 5, 6, 7, 8, 11, and 15 following injection of either triamcinolone or saline. Both cortisol and triamcinolone were as...
Velie BD, Hamilton NA, Wade CM.Different indicators of racing performance are commonly used in the racing industry to assess the genetic superiority of racing Thoroughbreds. However, how well these indicators predict the performance of future progeny or siblings varies depending on the population and circumstances in which the indicators were recorded or achieved. Objective: To identify heritable indicators of racing performance for horses racing in Hong Kong. Methods: Heritability analysis of racing performance traits. Methods: Performance data on the population of Thoroughbreds racing in Hong Kong between 3 September 2000...
Welsh CE, Lewis TW, Blott SC, Mellor DJ, Stirk AJ, Parkin TD.A retrospective cohort study of distal limb fracture and superficial digital flexor tendon (SDFT) injury in Thoroughbred racehorses was conducted using health records generated by the British Horseracing Authority (BHA) between 2000 and 2010. After excluding records of horses that had both flat and jump racing starts, repeated records were reduced to a single binary record per horse (n = 66,507, 2982 sires), and the heritability of each condition was estimated using residual maximum likelihood (REML) with animal logistic regression models. Similarly, the heritability of each condition was ...
Bani Hassan E, Mirams M, Ghasem-Zadeh A, Mackie EJ, Whitton RC.To gain a better understanding of the aetiology of articular surface collapse in horses with palmar osteochondral disease. Objective: To determine whether acceleration of focal bone resorption associated with reduced physical activity contributes to articular surface collapse in racehorses with palmar osteochondral disease. Methods: Cross-sectional study comparing metacarpal bones from horses at varying stages of race training. Methods: Metacarpal bones from 36 racing Thoroughbred horses were examined with high-resolution peripheral quantitative computed tomography to determine the proportion ...
Moreau P, Lavoie JP.To evaluate effects of thrombophlebitis of 1 or both jugular veins on athletic performance of horses. Methods: Retrospective case series. Methods: 91 horses with jugular vein thrombophlebitis. Methods: Medical records of horses with jugular vein thrombophlebitis examined between 1988 and 2005 were reviewed for signalment, history, clinical signs, diagnosis, and treatment. Performance was evaluated in 2 ways. A questionnaire was used to obtain a subjective assessment from the owner or trainer of the horse's performance after thrombophlebitis, compared with the performance before thrombophlebiti...
Cleary OB, Trumble TN, Merritt KA, Brown MP.To investigate the effects of exercise and osteochondral injury on concentrations of carboxy-terminal telopeptide fragments of type II collagen (CTX-II) in synovial fluid (SF) and serum of Thoroughbred racehorses and to compare findings with radiographic and arthroscopic scores of joint injury severity. Methods: 78 Thoroughbreds with (n = 38) and without (40) osteochondral injury. Methods: Serum and metacarpophalangeal or carpal joint SF samples were collected from noninjured horses before and at the end of 5 to 6 months of race training (pre- and postexercise samples, respectively) and from h...
Lopes MA, Dearo AC, Lee A, Reed SK, Kramer J, Pai PF, Yonezawa Y, Maki H, Morgan TL, Wilson DA, Keegan KG.OBJECTIVE To evaluate head, pelvic, and limb movement to detect lameness in galloping horses. ANIMALS 12 Thoroughbreds. PROCEDURES Movement data were collected with inertial sensors mounted on the head, pelvis, and limbs of horses trotting and galloping in a straight line before and after induction of forelimb and hind limb lameness by use of sole pressure. Successful induction of lameness was determined by measurement of asymmetric vertical head and pelvic movement during trotting. Differences in gallop strides before and after induction of lameness were evaluated with paired-sample statistic...
Ramzan PH, Palmer L, Powell SE.Fracture of the metacarpal/tarsal condyle is usually preceded by prodromal pathology. Early recognition of injury is desirable to minimise the risk of serious breakdown; however, the clinical and diagnostic characteristics of unicortical condylar fractures have been poorly documented to date. Objective: To describe the clinical, imaging and outcome features of racehorses in first opinion practice diagnosed with short unicortical fracture of the metacarpal/tarsal condyle. Methods: Retrospective case series. Methods: All flat racehorses sustaining a unicortical condylar fracture while under the ...
Tomlinson JE, Boston RC, Brauer T.To determine racing performance after surgery for colic in Thoroughbreds. Methods: Retrospective cohort study. Methods: 85 racing Thoroughbreds that survived to discharge following colic surgery and 170 race-matched reference horses. Methods: Earnings, starts, and earnings per start were compared between horses that underwent surgery and reference horses, the proportions of horses that returned to racing were analyzed, and career longevity was determined. Results: Among 85 racing Thoroughbreds that underwent colic surgery, 31 (36%) had primarily small intestinal lesions, of which 11 underwent ...
Weber JM, Dobson GP, Parkhouse WS, Wheeldon D, Harman JC, Snow DH, Hochachka PW.This study characterizes the effects of exercise on the cardiac output (Q) and the metabolic rate (VO2) of trained Thoroughbred racehorses. Heart rate, Q, and arteriovenous (a-v)O2 difference were measured at rest and at three levels of submaximal treadmill exercise (1.6 m/s walk and 3-4 m/s trot at 6% incline, and 6.5 m/s horizontal canter). Heart rate and (a-v)O2 difference were also measured during maximal exercise (12.5 m/s gallop, 5% incline) to obtain an estimate of maximum O2 uptake (VO2max). The walk, trot, and canter represented 25, 45, and 55% VO2max. Mean heart rate went from 48.9 (...
Bergmann IM.The idea of what is natural has particular relevance in the thoroughbred racing and breeding discourse. It guides breeding regulations; influences how the thoroughbreds' behaviour is perceived and has implications for husbandry, handling, training and racing practices. This study investigates how key industry and animal advocacy informants based in the US, Australia and the UK conceptualise naturalness within the context of common racing practices that potentially impact the horses' welfare. The informants were interviewed using semi-structured interviewing and photo-elicitation. Four common i...
Mignot CC, Pirottin D, Farnir F, de Moffarts B, Molitor C, Lekeux P, Art T.The effects of strenuous exercise and ex vivo stimulation of TLR3 and TLR4 pathways on the expression of six inflammatory genes in equine pulmonary leukocytes were investigated. The genes tested were interferon-beta (IFN-β), interleukin-1-beta (IL-1β), interleukin-6 (IL-6), interferon gamma-induced protein 10 (IP-10), chemokine (c-c motif) ligand 5 (RANTES) and tumor necrosis factor-alpha (TNF-α). We hypothesized that strenuous exercise would modulate basal gene expression on one hand and modulate the response to bacterial lipopolysaccharide (LPS) and to polyinosinic:polycytidylic acid (Pol...
Komosa M, Frackowiak H, Purzyc H, Wojnowska M, Gramacki A, Gramacki J.The study included 249 horses belonging to 3 horse breeds. Konik horses, comprising the first group, is an example of a breed similar to the extinct Tarpan. In our study, these horses were taken to be a primitive anatomical model of the horse body. The other groups comprised the Polish Half-bred horse and Thoroughbred horse. The biometric characteristics of the horses were compared based on 24 indices. The aim of the paper was to find a reduced set of indices that can be used to determine group membership of the horses. To do this, we used statistical methods to find the most important indices...
Hurtado C, Torres R, Pérez-Macchi S, Sagredo K, Uberti B, de Souza Zanatto DC, Machado RZ, André MR, Bittencourt P, Müller A.Anaplasma phagocytophilum is the causative agent of equine granulocytic anaplasmosis (EGA). This study aimed to perform serological and molecular surveys of A. phagocytophilum in thoroughbred horses from racecourses in Chile. Additionally, hematological findings related to A. phagocytophilum molecular positivity were addressed, and phylogenetic analysis of selected positive samples was performed. Complete blood count and msp2 gene real-time PCR were performed in 457 thoroughbred horses from three racecourses located in three different cities of Chile (Santiago, Viña del Mar and Concepción). ...
Cassimeris L, Engiles JB, Galantino-Homer H.Supporting Limb Laminitis (SLL) is a painful and crippling secondary complication of orthopedic injuries and infections in horses, often resulting in euthanasia. SLL causes structural alterations and inflammation of the interdigitating layers of specialized epidermal and dermal tissues, the lamellae, which suspend the equine distal phalanx from the hoof capsule. Activation of the interleukin-17A (IL-17A)-dependent inflammatory pathway is an epidermal stress response that contributes to physiologic cutaneous wound healing as well as pathological skin conditions. As a first test of the hypothesi...
Assenza A, Casella S, Giannetto C, Fazio F, Tosto F, Piccione G.The aim of this study was to evaluate the modifications of some haematological parameters and iron profile during an 80-day training program and their relationship with athletic performance of performance horses. Methods: During the training period, 20 Thoroughbreds were subjected to a standardised exercise test, previously standardised for gallopers to evaluate athletic performance. The test was performed immediately before the beginning of the training program (T0) and after 30 days (T30), 60 days (T60) and 90 days (T90). For each horse, their velocities at blood lactate concentrations of 2 ...
Crawford KL, Finnane A, Greer RM, Phillips CJC, Woldeyohannes SM, Perkins NR, Ahern BJ.There is international public concern regarding retirement of racehorses, including the reason for retirement and the outcome for horses after racing. However, there are currently no prospective studies investigating these factors. A recent independent inquiry in Queensland, Australia, highlighted that the true outcomes for horses after retirement from racing are largely unknown. Furthermore, there are currently no measures to monitor the outcome for racehorses and their welfare once they have left the care of the trainer. This study investigated these gaps in knowledge through a weekly survey...
Lankveld DP, Ensink JM, van Dijk P, Klein WR.Thrombophlebitis is a well-known complication of the use of long-term in-dwelling catheters. In humans, catheter material has been shown to strongly influence the occurrence of thrombophlebitis. In the horse, the influence of catheter material has been studied in healthy experimental animals, but information on the relative importance of this factor is lacking. To investigate which factors have most impact on the frequency of jugular vein thrombosis in post-surgical colic horses, a clinical study was performed on 38 animals. Horses were randomly divided into two groups. In one group a polytetr...
Tranquilli WJ, Thurmon JC, Neff-Davis CA, Davis LE, Benson GJ, Hoffman W, Lock TF.Plasma glucose and serum insulin concentrations in Thoroughbreds administered xylazine hydrochloride (1.1 mg/kg; IV) and ketamine hydrochloride (2.2 mg/kg; IV) at dosages sufficient to induce short periods of recumbency and anesthesia were measured. Samples of blood were collected from 6 adult horses before, during, and after the anesthetic period. Plasma glucose (mg/dl) was significantly increased above control (-30 minute concentration) from 15 to 150 minutes after xylazine administration with the peak value occurring at 30 minutes. Serum insulin (microU/ml) was significantly decreased from ...
Galisteo AM, Cano MR, Morales JL, Vivo J, Miró F.The influence of speed and height at the withers on some biokinematic stride parameters (linear, temporal and angular) was measured in 15 Spanish Thoroughbreds (Andalusian Purebred) trotted hand-led along a track; analysis was made of the correlation between speed and height at the withers and of some biokinematic parameters of equine locomotion. Both height at the withers and speed were positively and significantly correlated to the linear parameters examined. Temporal parameters did not reveal a significant correlation with the height at the withers. The correlations with the angular paramet...
Mills PC, Hills Y, Hills BA.To investigate the presence of surface-active phospholipid (SAPL, or surfactant) in equine tendon and tendon sheath fluid. Methods: The left front flexor tendon and sheath were removed from five Thoroughbred horses. Phospholipid was extracted from tendon sheath fluid using Folch reagent and quantified using spectroscopy. Transmission electron microscopy (TEM) was used to observe the tendon surfaces. Results: The presence of phospholipid (90.6 (SD 4.3) microg/ml) in tendon sheath fluid, plus the appearance of oligolamellar layers and lamellar bodies on the tendon surface were indicative of SAPL...
Hamond C, Martins G, Lilenbaum W.The infection by Leptospira in horses, in both its acute disease and subclinical forms, is very common, particularly in endemic regions. Therefore, the objective of this study was to evaluate the effects of subclinical leptospirosis in the athletic performance of racing thoroughbred horses. Athletic performance of 119 racing Thoroughbred horses from Rio de Janeiro, Brazil, was calculated by assigning a point value for the results in racing (performance index (PI)), and serology for leptospirosis was conducted. A total of 85 (71.4 %) horses showed reactive titers (≥ 100), and of which 52 had ...
Kelly PG, Reardon RJ, Johnston MS, Pollock PJ.Endoscopic examination of Thoroughbred (TB) yearlings is performed routinely to determine the suitability of horses for racing and to ensure that the conditions of sale are satisfied. However, previous research has demonstrated that resting endoscopic examination can be inaccurate in the diagnosis of functional pathology of the upper portion of the respiratory tract (URT). Objective: To investigate the feasibility of performing dynamic overground endoscopy in a group of TB yearlings and to compare the results of resting and dynamic endoscopic examination of the URT. Methods: Prospective cohort...
Sasaki N, Okamura K, Yamada H.To examine the effects of various doses of mosapride, a 5-hydroxytryptamine 4 receptor agonist, on motility of the small intestine and cecum in horses by use of electrical activity and to determine the dose that provides the optimal response. Methods: 6 healthy adult Thoroughbreds. Methods: Electrical activity of the small intestine and cecum was recorded before and after mosapride administration by use of an electrogastrograph. Mosapride (0.5, 1, 1.5, and 2 mg/kg) was dissolved in 200 mL of water and administered orally to horses through a nasogastric tube. Three hours after drug administrati...
Morrice-West AV, Hitchens PL, Walmsley EA, Wong ASM, Whitton RC.Understanding the relationship between the training practices of Thoroughbred racehorses and race performance is important to ensure advice given to trainers for injury prevention or management is practical and consistent. We assessed associations between intended volume and speed of gallop training (i.e., typical workloads for horses free of injury or other performance limiting conditions) and rest practices on official trainer career and previous season success rates (rate of wins and places, prizemoney per start). Sixty-six Australian Thoroughbred trainers were surveyed. Multivariable negat...
Kawasako K, Higashi T, Nakaji Y, Komine M, Hirayama K, Matsuda K, Okamoto M, Hashimoto H, Tagami M, Tsunoda N, Taniyama H.To evaluate the histologic diversity of epidermal laminae in hooves from horses without clinical signs of laminitis. Methods: Formalin-fixed samples of stratum internum obtained from the mid region of the dorsal aspect of the hoof wall from the forelimbs of 35Thoroughbred cadavers (including foals [n = 9], yearlings [5], 2 year olds [6], racing horses [5], and mares [10]). Methods: Paraffin-embedded laminar tissues were stained with H&E for the evaluation of architectural variety of primary epidermal laminae (PEL) and secondary epidermal laminae (SEL). For detection of cytokeratin (CK) express...